CELL TYPES AND CELL MODIFICATION Flashcards
are group of similar cells which perform a definite function
Tissues
types of animal tissues
EPITHELIAL TISSUES
CONNECTIVE TISSUES
MUSCLE TISSUES
NERVE TISSUES
cover body surfaces.
Epithelial Tissues
Outer layer of skin and the lining of organs
Epithelial Tissues
Also found in glandular tissue
Epithelial Tissues
Play roles in absorption, filtration, secretion, and protection against foreign substances
Epithelial Tissues
Usually fit closely together in continuous sheets
Special Characteristics of Epithelium
Exception: glandular epithelium
Special Characteristics of Epithelium
______ (Have no blood supply of their own)
Avascular
How do they get nutrients? (EPITHELIUM)
If well nourished, epithelial cells regenerate themselves easily.
Have one free (unattached) surface or edge called the apical surface
Special Characteristics of Epithelium
Exposed to body’s exterior or to the cavity of an internal organ
Apical surface
Lower surface of an epithelium rests on a ______
basement membrane
Structureless material secreted by both the epithelial cells and the connective tissue cells
basement membrane
Classification of Epithelium - first :
First: indicates relative number of cell layers
______ (one layer of cells)
Simple
________(more than one cell layer)
Stratified
Classification of Epithelium - second
Second: describes the shape of cells
_______ (cells flattened like scales)
Squamous
_______ (cube-shaped)
Cuboidal
_______ (shaped like columns)
Columnar
tissue is composed of flat, scale-like cells that usually forms membranes
Simple Squamous Epithelium
It lines the walls of blood vessels, pulmonary alveoli (shown here), and the lining of the heart, lung, and peritoneal cavities.
Simple Squamous Epithelium
This tissue is composed of a single layer of cube-like cells.
Simple Cuboidal Epithelium
It lines the walls of kidney tubules, covers the surface of ovaries, and is common in glands and their ducts.
Simple Cuboidal Epithelium
This tissue is composed of a single layer of tall cells.
Simple Columnar Epithelium
It often includes mucus-producing goblet cells.
Simple Columnar Epithelium
It often lines the digestive tract.
Simple Columnar Epithelium
Although this tissue appears stratified, it is actually composed of a single layer of cells of different types.
Pseudostratified Columnar Epithelium
Although their nuclei are found at different levels, each cell adjoins the basal membrane (BM).
Pseudostratified Columnar Epithelium
This tissue lines the larger respiratory passageways
Pseudostratified Columnar Epithelium
It is often ciliated (arrows).
Pseudostratified Columnar Epithelium
Main functions: absorption and secretion
Pseudostratified Columnar Epithelium
Ciliated variety lines respiratory tract
Pseudostratified Columnar Epithelium
Mucus produced by goblet cells traps dust and other debris
Pseudostratified Columnar Epithelium
Cilia propel mucus upward and away from the lungs
Pseudostratified Columnar Epithelium
The term “__________” refers to the layered arrangement of cells.
stratified
The outer layers of cells appear flat, but the inner cells vary in shape from cuboidal to columnar.
Stratified Squamous Epithelium
serves as a barrier to the outside environment in locations such as the skin, mouth, and esophagus.
Stratified Squamous Epithelium
is found in the ducts of sweat glands and surrounds Graafian follicles of ovaries.
Stratified Cuboidal Epithelium
Shape of cells depends upon the amount of stretching
Transitional Epithelium
It lines organs of the urinary system.
Transitional Epithelium
Some epithelial membranes are made up of cells with cilia, tiny projections that beat in unison to move mucus along the surface.
Ciliated Epithelium